Note: Descriptions are shown in the official language in which they were submitted.
POWER-ASSISTED RECLINING LIFT CHAIR WITH SPLIT SEAT
Related Application
[0001] The present application claims priority from U.S. Provisional Patent
Application No.
62/432,727, filed December 12, 2016.
Field of the Invention
[0002] The present invention is directed generally to lift chairs, and more
particularly to lift
chairs having reclining capability.
Background of the Invention
[0003] Conventionally, power-assisted lift chairs typically include a motor-
operated lift
mechanism for aiding invalids and those persons requiring assistance in
entering or exiting the
chair. More particularly, motor-operated lift mechanisms are interconnected
between a
stationary base assembly and a moveable chair frame. An example of such a
power-assisted
chair is disclosed in U.S. Patent. No. 4,993,777 to LaPointe.
[0004] Some power-assisted chairs also include separate linkage mechanisms
for permitting
the seat occupant to selectively actuate an extensible leg rest assembly
and/or produce reclining
angular movement of a seat assembly between "upright" and "reclined"
positions. However,
many power-assisted chairs which provide such a multi-functional combination
require the use
of multiple motors for driving (i.e., pushing) the separate linkages which
results in extremely
large and expensive chair units yet still having limited reclining options.
Moreover, such power-
assisted chairs typically incorporate a drive mechanism which employs both a
power "drive"
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function (i.e., for extending the leg rest, lifting the chair, and/or
reclining the chair) and a power
"return" function for returning the chair to the normal seated position.
[0005] One power-assisted lift chair that employs a single actuator is
disclosed in U.S. Patent
No. 5,730,494 to LaPointe et al. This chair employs a linear actuator with a
carrier, wherein the
carrier moves rearwardly relative to the base to lift the chair from its
upright position. The
carrier moves forwardly to move the chair from its upright position to its TV
and fully reclined
positions. Another lift chair employing a single actuator is discussed in U.S
Patent No.
8,783,764 to Murphy.
[0006] Still another power-assist lift chair is discussed in U.S. Patent
No. 7,540,565 to
Lipford, which employs a "split" seat. The front portion of the seat pivots to
slope downwardly
from back to front as the chair rises to the lift position. This motion can
provide support surfaces
for the occupant that eases rising from the chair.
[0007] Those skilled in this art will appreciate that additional chair
designs with improved
functionality may be desirable.
Summary
[0008] As a first aspect, embodiments of the invention are directed to a
seating unit,
comprising: a base configured to rest on an underlying surface; a frame
including opposed arms;
a backrest; a seat, the seat including a front portion and a rear portion; a
footrest; a lift
mechanism pivotally attached to the base, the frame and the seat; a lift drive
unit attached to the
lift mechanism; a reclining mechanism pivotally attached to the seat and the
backrest; a recline
drive unit attached to the reclining mechanism; a footrest mechanism pivotally
attached to the
base and the footrest; and a footrest drive unit attached to the footrest
mechanism. The lift
mechanism is configured to control the movement of the frame, seat and
backrest between an
upright position, in which the backrest is generally upright, the front and
rear portions of the seat
are generally horizontal, the footrest is generally upright and positioned
below the seat, and the
backrest, seat and frame are at a first elevation, and a lift position, in
which the backrest is
generally upright, and rear portion of the seat is generally horizontal, and
the backrest, rear
portion of the seat and frame are at a second elevation that is higher than
the first elevation, and
the front portion of the seat is generally vertically disposed. The reclining
mechanism is
configured to control the movement of the backrest and seat between the
upright position and a
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reclined position, in which the backrest takes a shallower angle relative to
horizontal than in the
upright position. The footrest mechanism is configured to control the movement
of the footrest
between the upright position and an extended position, in which the footrest
is generally
horizontally disposed and positioned forwardly of the seat.
[0009] As a second aspect embodiments of the invention are directed to a
seating unit
comprising: a base configured to rest on an underlying surface; a frame
including opposed arms;
a backrest; a seat, the seat including a front portion and a rear portion; a
footrest; a lift
mechanism pivotally attached to the base, the frame and the seat; a lift drive
unit attached to the
lift mechanism; a reclining mechanism pivotally attached to the seat and the
backrest; a recline
drive unit attached to the reclining mechanism; a footrest mechanism pivotally
attached to the
base and the footrest; and a footrest drive unit attached to the footrest
mechanism. The lift
mechanism is configured to control the movement of the frame, seat and
backrest between an
upright position, in which the backrest is generally upright, the front and
rear portions of the seat
are generally horizontal, the footrest is generally upright and positioned
below the seat, and the
backrest, seat and frame are at a first elevation, and a lift position, in
which the backrest is
generally upright, and rear portion of the seat is generally horizontal, and
the backrest, rear
portion of the seat and frame are at a second elevation that is higher than
the first elevation, and
the front portion of the seat is generally vertically disposed. The reclining
mechanism is
configured to control the movement of the backrest and seat between the
upright position and a
reclined position, in which the backrest takes a shallower angle relative to
horizontal than in the
upright position. The footrest mechanism is configured to control the movement
of the footrest
between the upright position and an extended position, in which the footrest
is generally
horizontally disposed and positioned forwardly of the seat. The footrest
mechanism is decoupled
from the lift mechanism such that operation of the lift mechanism does not
move the footrest
relative to the base. The footrest mechanism is decoupled from the reclining
mechanism such
that operation of the reclining mechanism does not move the footrest relative
to the base.
[0010] As a third aspect, embodiments of the invention are directed to a
seating unit
comprising: a base configured to rest on an underlying surface; a frame
including opposed arms;
a backrest; a seat, the seat including a front portion and a rear portion; a
footrest; a lift
mechanism pivotally attached to the base, the frame and the seat; a lift drive
unit attached to the
lift mechanism; a reclining mechanism pivotally attached to the scat and the
backrest; a recline
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drive unit attached to the reclining mechanism; a footrest mechanism pivotally
attached to the
base and the footrest; and a footrest drive unit attached to the footrest
mechanism. The lift
mechanism is configured to control the movement of the frame, seat and
backrest between an
upright position, in which the backrest is generally upright, the front and
rear portions of the seat
are generally horizontal, the footrest is generally upright and positioned
below the seat, and the
backrest, seat and frame are at a first elevation, and a lift position, in
which the backrest is
generally upright, and rear portion of the seat is generally horizontal, and
the backrest, rear
portion of the seat and frame are at a second elevation that is higher than
the first elevation, and
the front portion of the seat is generally vertically disposed. The reclining
mechanism is
configured to control the movement of the backrest and seat between the
upright position and a
reclined position, in which the backrest takes a shallower angle relative to
horizontal than in the
upright position. Tthe footrest mechanism is configured to control the
movement of the footrest
between the upright position and an extended position, in which the footrest
is generally
horizontally disposed and positioned forwardly of the seat. The lift mechanism
is decoupled
from the reclining mechanism, such that an angle between the backrest and the
underlying
surface does not substantially change during operation of the lift mechanism.
The footrest
mechanism is decoupled from the lift mechanism such that operation of the lift
mechanism does
not move the footrest relative to the base.
Brief Description of the Figures
[0011] FIG. 1 is a side view of a reclining lift chair according to
embodiments of the
invention, with the chair shown in its upright position.
[0012] FIG. 2 is a side view of the chair of FIG. 1 shown in the lift
position.
[0013] FIG. 3 is a side view of the chair of FIG. 1 shown with the backrest
in the reclined
position and the footrest in the extended position.
[0014] FIG. 4 is a top view of the chair of FIG. 1 in the upright position.
[0015] FIG. 5 is a side view of the lift, reclining and footrest mechanisms
of the chair of
FIG. 1 shown in the upright position.
[0016] FIG. 6 is a side view of the lift, reclining and footrest mechanisms
of the chair of
FIG. 1 shown in the lift position.
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[0017] FIG. 7 is a side view of the lift, reclining and footrest mechanisms
of the chair of
FIG. 1 shown with the backrest in the reclined position and the footrest in
the extended position.
[0018] FIG. 8 is a side view of the lift and reclining mechanisms of the
chair of FIG. 1
shown in the upright position.
[0019] FIG. 9 is a side view of the lift and reclining mechanisms of the
chair of FIG. 1
shown in the lift position.
[0020] FIG. 10 is a side view of the lift and reclining mechanisms of the
chair of FIG. 1
shown with the backrest in the reclined position.
[0021] FIG. 11 is a side view of the footrest mechanism of the chair of
FIG. 1 shown in its
retracted position.
[0022] FIG. 12 is a side view of the footrest mechanism of the chair of
FIG. 1 shown in its
extended position.
Detailed Description
[0023] The present invention will be described more particularly
hereinafter with reference
to the accompanying drawings. The invention is not intended to be limited to
the illustrated
embodiments; rather, these embodiments are intended to fully and completely
disclose the
invention to those skilled in this art. In the drawings, like numbers refer to
like elements
throughout. Thicknesses and dimensions of some components may be exaggerated
for clarity.
Well-known functions or constructions may not be described in detail for
brevity and/or clarity.
[0024] Unless otherwise defined, all terms (including technical and
scientific terms) used
herein have the same meaning as commonly understood by one of ordinary skill
in the art to
which this invention belongs. It will be further understood that terms, such
as those defined in
commonly used dictionaries, should be interpreted as having a meaning that is
consistent with
their meaning in the context of the relevant art and will not be interpreted
in an idealized or
overly formal sense unless expressly so defined herein.
[0025] In addition, spatially relative terms, such as "under'', "below",
"lower", "over",
"upper" and the like, may be used herein for ease of description to describe
one element or
feature's relationship to another element(s) or feature(s) as illustrated in
the figures. It will be
understood that the spatially relative terms are intended to encompass
different orientations of
the device in use or operation in addition to the orientation depicted in the
figures. For example,
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if the device in the figures is inverted, elements described as "under" or
"beneath'' other elements
or features would then be oriented "over" the other elements or features.
Thus, the exemplary
term "under" can encompass both an orientation of over and under. The device
may be
otherwise oriented (rotated 90 degrees or at other orientations) and the
spatially relative
descriptors used herein interpreted accordingly.
[0026] The terminology used herein is for the purpose of describing
particular embodiments
only and is not intended to be limiting of the invention. As used herein, the
singular forms "a",
"an" and "the" are intended to include the plural forms as well, unless the
context clearly
indicates otherwise. It will be further understood that the terms "comprises"
and/or
"comprising," when used in this specification, specify the presence of stated
features, integers,
steps, operations, elements, and/or components, but do not preclude the
presence or addition of
one or more other features, integers, steps, operations, elements, components,
and/or groups
thereof. As used herein the expression "and/or" includes any and all
combinations of one or
more of the associated listed items.
[0027] Where used, the terms "attached", "connected", "interconnected",
"contacting",
"coupled", "mounted" and the like can mean either direct or indirect
attachment or contact
between elements, unless stated otherwise.
[0028] In addition, some components of the seating units described herein
(particularly
mechanisms thereof) are illustrated herein as a series of pivotally
interconnected links or
members. Those skilled in this art will appreciate that the pivots between
links or other
components can take a variety of configurations, such as pivot pins, rivets,
bolt and nut
combinations, and the like, any of which may be suitable for use with the
present invention.
Also, the shapes and configurations of the links themselves may vary, as will
be understood by
those skilled in this art. Further, some links may be omitted entirely in some
embodiments, and
additional links may be included in some embodiments.
[0029] Referring now to the drawings, a reclining lift chair, designated
broadly at 10, is
shown in FIGS. 1-4. The chair includes a base 12 that rests on an underlying
surface, a frame
14, a seat 16, a backrest 18, and rear and front footrests 20a, 20b. These
structures are
interconnected with a pair of reclining mechanisms 21, a pair of footrest
mechanisms 19, and a
pair of lift mechanisms 23 (see FIG. 3). These components are discussed in
greater detail below.
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[0030] Referring now to FIGS. 3 and 4, the base 12 includes a pair of side
rails 24 and three
cross-members 26a, 26b, 26c that extend between the side rails 24. Two feet 22
are mounted to
the underside of each side rail 24. A lift actuator mounting bracket 28 is
mounted to the
rearmost cross-member 26a, and a footrest mounting bracket 33 is mounted to
the cross-member
25b. Covers 35 are mounted above the side rails 24 and are spanned by a cross-
rail 35a.
[0031] Referring still to FIGS. 3 and 4, the frame 14 includes arms 29 and
a rear panel 31
that spans the arms 29. Each arm 29 comprises an inner panel 40 and an outer
panel 42 that are
separated by spacers 41, thereby forming a cavity 43 within each arm 29.
[0032] Referring to FIGS. 2, 3 and 4, the seat 16 is split into front and
rear portions 202,
204. The rear portion 202 has a platform 206 that sits atop cross-members 208.
The cross-
members 208 are fixed to mounting panels 210 that are in turn fixed to the
inner panels 40 of the
arms 29. Angle brackets 212 are attached to the underside of the cross-members
208. A seat
link 214 is fixed to each angle bracket 212. The front portion 204 of the seat
16 has a platform
216 that is mounted on angle brackets 218. The angle brackets 218 are
pivotally attached to
connecting brackets 220 at a pivot 222; the connecting brackets 220 are fixed
to the front ends of
the angle brackets 212 of the rear portion 202. Upholstery (not shown)
overlies the platforms
206, 216.
[0033] The lift mechanisms 23 are configured to move the chair 10 between
an upright
position (shown in FIGS. 1, 4, 5 and 8), in which the backrest 18 is generally
upright and defines
a first backrest angle relative to horizontal, both portions 204, 204 of the
seat 16 are generally
horizontal, and the footrests 20a, 20b are retracted below the seat 16, and a
lift position (FIGS.
2, 6 and 9), in which the frame 14 and the seat 16 are raised, with the rear
portion 202 of the seat
remaining generally horizontal and the front portion 204 of the seat 16 being
generally vertical.
For clarity, the lift mechanisms 23 will be described first with respect to
the lift position (FIGS.
2, 6 and 9).
[0034] Also, each of the lift mechanisms 23 is a mirror image of the other
lift mechanism 23
relative to a vertical plane P that extends from the front of the chair 10 to
the rear centered
between the arms 29 (see FIG. 4). In the interest of brevity, only one lift
mechanism 23 will be
described herein, with the understanding that the discussion is equally
applicable to its mirror
image lift mechanism 23.
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[0035] Referring now to FIGS. 6 and 9, the lift mechanism 23 includes a
lift mounting plate
44 that is mounted to the upper surface of the cross-member 26c and a small
member 26d. A
rear lift link 36 is pivotally mounted to the lift mounting plate 44 at a
pivot 38. A front lift link
32 is pivotally mounted to the lift mounting plate 30 at a pivot 34. Each of
the front and rear lift
links 32, 36 extends upwardly and slightly rearwardly from its respective
pivot 34, 38 to a
respective pivot 50, 52 with the seat link 214.
[0036] A lift actuator 54 is pivotally mounted to the lift actuator
mounting bracket 28 at a
pivot 55. The actuator 54 includes a motor 56, a sleeve 57 that extends
forwardly and upwardly
from the motor 56, and a rod 58 that is retractable into and extendable away
from the sleeve 57.
The forward end of the rod 58 is attached at a pivot 60 to a bracket 61 that
is fixed to a cross-
member 62. The cross-member 62 is attached at each end to a bracket 63 fixed
to each rear lift
link 36. Also, a drawing link 64 is pivotally attached at one end to the front
lift link 32 at a pivot
65 and to the angle bracket 218 at a pivot 66.
[0037] As can be seen in FIGS. 1, 5 and 8, in the upright position the
front and rear lift links
32, 36 extend rearwardly from their respective pivots 34, 38 with the lift
mounting plate 44. The
rod 58 of the lift actuator 54 is retracted into the sleeve 57. The drawing
link 64 is extends
upwardly and forwardly from the pivot 65 to support the front end of the front
portion 204 of the
seat 16, such that the front portion 204 is generally horizontal and aligned
with the rear portion
202 to form a smooth, horizontally-disposed seating surface. The lift
mechanism 23 is
maintained in this position by the interaction between a pin 44a on the lift
mounting plate 44 and
the rear edge of the front lift link 32.
[0038] To move the chair 10 from the position of FIGS. 1, 5 and 8 to the
lift position of
FIGS. 2, 6 and 9, an occupant of the chair 10 actuates the lift actuator 54
(typically via a remote
control box, console, handheld unit or the like associated with the lift
actuator 54). Actuation of
the lift actuator 54 extends the rod 58 from the sleeve 57, which forces the
rear lift link 36 to
pivot clockwise (from the vantage point of FIGS. 1, 5 and 8) about the pivot
38 and cause the
seat link 214 (and in turn the rear portion 202 of the seat 16) to rise and
move forwardly relative
to the base 12. Movement of the seat link 214 causes the front lift link 32 to
pivot clockwise
about the pivot 34. As the front lift link 32 pivots, the presence of the
drawing link 32 draws the
angle bracket 218 (and consequently the front portion 204 of the seat 16)
clockwise about the
pivot 222, thereby rotating the front portion 204 of the seat 16 relative to
the rear portion 202 to a
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generally vertical orientation (see FIGS. 2, 6 and 9). Movement to the lift
position ceases when
the rod 58 is fully extended.
[0039] Notably, the backrest 18 generally maintains its angular orientation
relative to the
base 12 and to the front portion of the seat 16 as the chair 10 moves to the
lift position. The
absence of angular movement can prevent the sensation that the chair is
"tipping" or "throwing"
the occupant from the chair 10 during the lifting movement. Also, the pivoting
of the front
portion 204 of the seat 16 can facilitate dismounting from the chair 10.
[0040] Referring now to the reclining mechanisms 21, each of the reclining
mechanisms 21
is a mirror image of the other reclining mechanism about the plane P. In the
interest of brevity,
only one reclining mechanism 21 will be described herein, with the
understanding that the
discussion is equally applicable to the other reclining mechanism 21. Also,
the reclining
mechanism will be described first with respect to the fully reclined position
(FIGS. 3, 7 and 10)
in order to illustrate more easily the interconnection of the various links
thereof.
[0041] The reclining mechanism 21 includes an angled backpost 160 that is
fixed to the
backrest 18. The front end of the backpost 160 is attached to the upper rear
end of the seat link
214 at a pivot 162. A bracket 164 is fixed to the lower rear end of the
backpost 160; a cross-
member 166 extends between the brackets 164 on either side of the chair 10. A
backpost
extension 168 is fixed to the lower end of the backpost 160 and extends
forwardly and
downwardly therefrom. Also, a control link 176 with a slot 176a is attached to
the backpost 160
at a pivot 178 that is substantially collinear with the cross-member 166. A
pin 214a mounted on
the seat link 214 is received in the slot 176a.
[0042] A reclining actuator 170 includes a motor 172 and a rod 174 that
extends from a
sleeve 173. The rod 174 is attached at a pivot 175 to the backpost extension
168. The motor 172
is attached via a pivot 177 to a bracket 179 that is fixed to the forwardmost
cross-member 208.
[0043] In the upright position of FIGS. 1, 5 and 8, the upper end of the
backpost 160 is
generally upright, with a slight rearward pitch for comfort. The rod 174 is
extended from the
sleeve 173. The control link 176 extends downwardly and forwardly from the
pivot 178 such
that the pin 214a on the seat link 214 is positioned in the lower end of the
slot 176a.
[0044] To recline the backrest 18 relative to the seat 16 from the upright
position of FIGS. 1,
and 8 to the reclined position of FIGS. 3, 7 and 10, the occupant of the chair
10 actuates the
reclining actuator 170 (typically via a remote device of the type described
above with respect to
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the lift mechanism 23). The rod 174 retracts into the sleeve 173, thereby
drawing the lower end
of the backpost extension 168 forward. This motion pivots the backpost 160
counterclockwise
about the pivot 162, which reclines the backpost 160 and attached backrest 18
relative to the seat
link 214 and attached seat 16. Reclining motion ceases when the control link
176 moves
sufficiently forwardly and downwardly that the pin 214a strikes the upper end
of the slot 176a.
[0045] Notably, the reclining mechanism 21 is configured to allow the
backrest 18 to
reclined to a sufficiently shallow angle relative to horizontal (e.g., 0 to 35
degrees) that it can
provide a comfortable sleeping position for the occupant. This capability can
render the chair 10
particularly suitable for use in health care facilities, retirement
facilities, and the like. It should
also be noted that the reclining mechanism 21 can take the backrest 18 to any
desired angle
between the upright position of FIGS 1, 5 and 8 and the fully reclined
position of FIGS. 3, 7 and
10.
[0046] Referring now to FIGS. 3, 7 and 12, the footrest mechanisms 19
interconnect the
footrests 20a, 20b with the frame 14 (FIGS. 3, 7 and 12 show the footrests
20a, 20b in their
extended position for clarity of description). Like the lift and reclining
mechanisms 23, 21, each
of the footrest mechanisms 19 is a mirror image of the other footrest
mechanism 19 relative to
the vertical plane P. In the interest of brevity, only one footrest mechanism
19 will be described
herein, with the understanding that the discussion is equally applicable to
its mirror image lift
mechanism 23.
[0047] As best seen in FIGS. 7 and 12, a footrest adapter 68 is fixed to
the lift mounting
panel 44. An upper footrest swing link 72 is attached to a front portion of
the seat adapter 66 at a
pivot 74 and extends downwardly and forwardly therefrom. A lower footrest
swing link 76 is
attached to the footrest adapter 68 at a pivot 78 that is located rearwardly
and downwardly from
the pivot 74; the lower footrest swing link 76 extends generally forwardly
from the pivot 78. An
upper footrest extension link 80 is attached to the forward end of the lower
footrest swing link 76
at a pivot 82 and extends forwardly and upwardly therefrom. Also the upper
footrest extension
link 80 is attached to the upper footrest swing link at a pivot 84. A lower
footrest extension link
86 is attached to the forward end of the upper footrest swing link at a pivot
88 that is positioned
above and forward of the pivot 84 and extends upwardly and forwardly therefrom
generally
parallel with the upper footrest extension link 80. A front footrest bracket
90 is generally
horizontally disposed and is attached to the lower footrest extension link 86
at a pivot 92. A
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front footrest stabilizing link 89 is attached at a pivot 94 to the front
footrest bracket 90. The
front footrest 20b is mounted on the outer footrest bracket 90. A rear
footrest bracket 96 is
attached at its lower, forward end to the front footrest stabilizing link 89
at a pivot 91. lower
footrest extension link 86 at a pivot 98. At its opposite end, the rear
footrest bracket 96 supports
the front footrest 20a and is also attached to the upper footrest extension
link 80 at a pivot 99.
The rear ottoman bracket 96 is also pivotally attached to the lower footrest
extension link 86 at a
pivot 97.
[0048] Referring still to FIGS. 3, 7 and 12, the chair 10 includes a linear
actuator 112 that
drives the rear and front footrests 20a, 20b between their retracted and
extended positions. The
actuator 112 includes a motor 114 and a retractable rod 118. The motor 114 is
attached at a pivot
50 to the upper end of a tab 50 mounted onto the cross-member 25b. The rod 118
of the actuator
112 is attached at a pivot 122 to a projecting bracket 146 that extends from a
cross-member 148
between the lower footrest swing links 76.
[0049] As can be seen in FIGS. 1, 5 and 11, in the retracted position, the
rod 118 of the
actuator 112 is retracted. Because the rod 118 is in its retracted position, a
pantographic linkage
formed by the upper and lower footrest swing links 72, 76 and the upper and
lower footrest
extension links 80, 86 is folded under the seat 14, which positions the
footrest 20a underneath a
forward portion of the seat 16 and the footrest 20b just forward of and below
the seat 16 in a
vertical orientation.
[0050] To move the footrests 20a, 20b from their retracted positions in
FIGS. 1, 5 and 11 to
their extended positions of FIGS. 3, 7 and 12, an occupant of the chair 10
actuates the actuator
112, which causes the rod 118 to begin to extend away from the motor unit 114,
thereby driving
the lower footrest swing link 76 counterclockwise about the pivot 78. Rotation
of the lower
footrest swing link 76 forces the upper footrest extension link 80 forward,
which in turn draws
the upper footrest swing link 72 counterclockwise around the pivot 74. Also,
the lower footrest
extension link 86 moves forwardly more than the upper footrest extension link
80, such that the
rear footrest bracket 96 rotates counterclockwise about the pivot 97. The
rotation of the rear
footrest bracket 96 causes the rear footrest 20a to rotate from a vertical
orientation to a horizontal
orientation.
[0051] Also, the extension of the lower footrest extension link 86 and the
rotation of the rear
footrest bracket 96 forces the lower end of the rear footrest bracket 96
forward. This action
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forces the front footrest stabilizing link 89 forward, which extends and
rotates the front footrest
bracket 90, and in turn the front footrest 20b, to a generally horizontal
disposition in front of the
seat 16.
[0052] All of the lift, reclining and footrest mechanisms are decoupled in
the illustrated
embodiment and therefore may move independently of each other. It is
contemplated that two or
three of the lift, reclining and footrest actuators (or drive units other than
the illustrated linear
actuators) may be actuated from a common device (as an example, a single
handheld device with
multiple toggle buttons or joysticks to actuate each of the actuators
individually). Also, in some
embodiments, a cut-off or safety switch or similar actuation blocker may be
included to prevent
either or both of the reclining mechanism 21 and the footrest mechanism 19
from moving to the
reclined or extended positions when the lift mechanism 23 is actuated.
Further, such a safety
switch may be configured so that the lift mechanism 23 cannot be actuated
unless the reclining
mechanism 21 is the upright position and the footrest mechanism 19 is in the
retracted position
(i.e., the chair 10 cannot move to the lift position unless it is in the
condition shown in FIG. 1).
[0053] It is also noteworthy that, as the seat 16 and backrest 18 move from
the upright
position to the lift position, the footrest mechanisms 19 and footrests 20a
remain in the their
retracted position on the base 12 and are not lifted. As such, when the seat
16 and backrest are
lowered from the lift position to the upright position, the footrests 20a, 20b
are already out of the
way and pose no threat to an occupant as he is seating himself with the aid of
the lift mechanisms
23.
[0054] The foregoing is illustrative of the present invention and is not to
be construed as
limiting thereof. Although exemplary embodiments of this invention have been
described, those
skilled in the art will readily appreciate that many modifications are
possible in the exemplary
embodiments without materially departing from the novel teachings and
advantages of this
invention. Accordingly, all such modifications are intended to be included
within the scope of
this invention as defined in the claims. The invention is defined by the
following claims, with
equivalents of the claims to be included therein.
12
